Throughout his lifetime, Malling Hansen was also involved in other innovativeprojects, although all were related to his everyday work with the deaf. In 1867, he came up with the idea for the world's first true typewriter1, the "typing ball" (Danish: skrivekugle), to which he was granted a patent in 1870. The typing ball was produced in many different versions, across the world. In 1872, a version of the typing ball, called the tachygraph, made especially for telegraphy, was presented by Malling Hansen. The typing ball, for all its charm2, was soon surpassed by the AmericanRemington typewriter (1873).

During the 1880s, Malling Hansen published a series of seminal discoveries about the growth and development of children, based on detailed measurements of diet, height and weight of pupils at the Deaf-Mute Institute. It turned out that there were regular periods in the growth of children, "growth spurts". Previously, it had been believed that children grew at a steady pace.